It is interesting that Stanley Darwell, Father, was the Informant of the birth. I wonder whether they had to show ID in those days to give information for a legal document. - But it does strengthen the case for his name being accurate. It would be good to see his signature on the original document, to see whether he had two initials.
It is also interesting that Dora was recorded as married, although this was probably to cover up an illegitimate birth (assumption because the baby was given away).
You are depending on someone's memory for the Colonel from the IOM - they might have heard the IOM for Dora, and confused to whom it applied. Also they might have increased the importance of their military man, to make him sound better to a daughter.
In the "Description Medal cards" from WW1 there was Darwell, John S:
Corps Regiment No Rank
Manchester Regiment 400232 Private
Liverpool Regiment 94412 Private
This was the death I noticed before, which I suggested for a will:
Surname Given Name District Volume Page
Deaths Jun 1928
Darwell John S 56 Nantwich 8a 402
[Not far from Bangor.]